Hi All.

Recently put in a Wester's tune for my 03 Denali XL withRadix and Headers.

Vehicle perked up considerably but notice when bag it on highway (not even towing) that pyrometer is at max reading (16 or so). Not good for an extended period of time.

Same thing when towing and attempting to maintain speed up inclines (approx 75 mph, 4500 lb ultralight trailer).

Is the answer simply to back off to say around 65, or should I expect to be able to do a 1-2 min pull up a hill at speed. And further, would the addition of the Volant Ram Air kit to my Volant Box help? Or perhaps a milder tune (told Lyndon would be towing). Should still tow in tow mode right? Should gear down to 3?? from D? Thought tow mode handled all that.

A bit concerned. Vacation and tow through mountains in a week and a bit.

Sorry for the rapid fire questions. Searched "pyrometer too hot" but did not get much.

Thanks

D

 

That is a good ???

 

Whats your tranny temp ?

While towing I would be concerned with you tranny temp. BAcking down while towing up mountains will save your tranny.

 

sounds like you might want to run a wide band on it to see if your a/f is in the safe range.

 

Check your a/f and also if you are towing up hill for extended periods you chould get a tranny cooler on it. I believe the denalis come with a factoryr one but they suck its like a 3"X6" cooler.

 

Get it on a wide band, 1600 is way hot, guessing you are pretty lean, the tune may just be a little to aggressive. When I first got my Procharger my EGT's were consistantly over 1200 on the highway and easily hit 1400-1600 towing (I was running stock injectors and an FMU), when I dynoed the truck on a wide band I found out it was running pretty lean (14-15:1) in the upper RPM's. Since then I got 42lb injectors and had it retuned and my typical EGT on the highway is under 1200 and NEVER over 1400 and I tow an 8500lb+ travel trailer over some pretty big hills, keeping my foot on the floor and 3500+ RPM for minutes at a time. Also Where is the probe for your EGT mounted? Mine is right on the manifold.

 

I have alwas worryed about my exhaust temps too, but me being turboed is a little different from SC when exhaust temps are being compared. Anyway with the 5.3 I seen exhaust temps hit 1400 with out towing but up a hill. now with the 6.0 the exhaust temp gauge goes up almost as fast as the boost gauge, My only guess is the 5.3 cats with 88,000 miles don't like the 6.0, so what year is you truck blowndenalixl? could exhaust restriction be a probplem?

 

Thanks for the input guys.

My Denali XL is a 2003. I have 42 lb injectors, jba headers, flopro muffler, and Volant Airbox as well (should have mentioned that originally.

Sorry a bit ignorant here, but what is A/F?

Also in talking with Lyndon at lunch he suggested that it depended a fair bit on where the pyrometer sensor was located.

Thanks

D

 

pyro location does play a big part in you readings, you will see hotter readings the closer to the exhaust manifolt you are.

A/F+ Air Fuel ratio, running at WOT you what to see 10.5 ish A/F to be safe. Safe A/F kinda depends on your set-up too. you may be able to run leaner.

 

so where can we look to find the "perfect spot" for a pyrometer? is there a thread on it.......gone to search.